Spending hours defending his security policies on television, scrapping a ¥252 billion ($2 billion) Olympic stadium plan and playing up concerns about China, Prime Minister Shinzo Abe is battling to claw back a slide in support.

His approval rating plunged below 40 percent in polls taken after he pushed bills through the Diet last week to expand the role of the Self-Defense Forces. While he's at no immediate risk of being ousted, he must avoid dropping into the danger zone around the 20 percent mark at which successive leaders have been toppled at the ballot box or by their party.

That means assuaging public fears over his defense bills and returning the focus to his economic policies, which helped propel him to a second election win in December.